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1.
决定中国区域生态系统生产能力指数的影响因子主要有两类:一是下垫面的影响,山区、丘陵的生产能力高于平原区,在具备生产能力的土地生态类型中,林地生产能力最高,耕地次之,草地最低;二是气候因子的影响,季风气候决定了我国生态系统生产能力的空间分布.呈现西北-东南逐级递增的趋势,造成这种空间分布的主要因素是季风气候造成的降水空间分布.同时,温度也在一定程度上影响了我国生态系统的生产能力,尤其是东部地区.降水对生态系统生产能力的影响强度较温度大.  相似文献   

2.
生态系统服务价值的研究是目前生态学研究的热点之一。本文基于生态系统服务功能价值理论,根据银川市土地利用变化的情况,定量估算了其土地生态系统为人类提供服务的经济价值。结果表明,1996—2006年银川市生态系统服务价值变化的总态势是先增后减,生态系统服务功能在城市化过程中受到较大的影响。  相似文献   

3.
以湟水流域为研究区,从生态敏感性、土地利用生态适宜性角度分析流域土地资源利用合理性,以生态用地为约束评价土地资源环境承载能力。结果表明:流域内中度敏感区占比最高,为4170%,主要处于以高、中覆盖度草地、林地、水域及未利用土地为主的浅山区和脑山区的相交区域;高度敏感区占比1513%,集中分布于以林地为主的脑山区。9887%的城乡工矿居民用地处于非敏感区和一般敏感区内,流域内城乡建设用地类型空间布局总体上与生态环境相适应,布局合理;水域、高覆盖度草地和林地的改变会对生态环境造成很大影响,不适宜开发利用。  相似文献   

4.
准噶尔盆地西北部引水工程的建成和运行,对工程沿线区域土地资源的利用方式产生了深远的影响,也改变了该区域以土地资源为载体的生态系统的结构和生态环境的价值。以Constanza等人对全球各类生态系统单位面积服务价值的测算为依据,根据准噶尔盆地西北部引水工程沿线影响区2000年和2002年LandsatTM卫星影像解译数据,对工程建设和运行的生态环境效益予以估算。结果表明:引水工程的建设运行使工程影响区内生态系统的生态环境效益增加了2657 14×104 (约合22054 26×104元人民币),其中水域及耕地生态系统生态效益的增加是研究区生态效益增加的主要方面。  相似文献   

5.
基于改进PSR模型的长株潭地区土地生态系统健康评价研究   总被引:1,自引:0,他引:1  
基于改进的PSR模型构建土地生态系统健康评价指标体系,运用组合赋权法确定指标权重,对长株潭地区及其各县(市、区)的土地生态系统健康进行定量分析和评价。研究表明:2002—2014年,长株潭地区土地生态系统健康综合指数由5002下降至4132,呈波动下降趋势,主要影响因素为单位耕地农药施用量、单位耕地化肥施用量、水土流失比率、森林覆盖率、环保投资额占GDP比例、封山育林及当年造林面积。该地区15个县(市、区)的土地生态系统健康状况呈现明显的时空差异,1个属于综合指数快速上升区,6个属于基本稳定区,7个属于慢速下降区,1个属于快速下降区。  相似文献   

6.
农村土壤利用城市生活垃圾施肥的调查研究   总被引:2,自引:0,他引:2  
对城市生活垃圾和农村利用垃圾施肥及利用垃圾养殖蚯蚓的情况作了深入的调查研究.调查结果表明城市生活垃圾在一定条件下能为农业提供良好的有机肥料,改善农村土壤结构,提高土壤中多种肥分含量.根据本地城市生活垃圾特征和土地资源情况,堆肥和填埋相结合处理城市生活垃圾不失为符合山区实际的一种方法.  相似文献   

7.
为研究2000—2015年丹江湿地国家级自然保护区及其内外生态状况变化和保护成效,基于高分1号数据生产的2m高分辨率遥感影像数据对丹江湿地国家级自然保护区2015年人类活动状况进行分析,基于30 m分辨率的4期TM遥感影像生产的土地覆被数据和基于Modis遥感影像生产的植被覆盖度数据,对淅川县、丹江湿地国家级自然保护区及其核心区的土地覆被状况、土地覆被转类指数及其土地覆被转类途径的主导程度和3个相关区域范围内的生态系统质量以及不同区域土地覆被变化的主要变化原因进行分析。结果表明,保护区核心区的格局和质量在该区域处于最优,且土地覆被变化状况也以核心区转类指数最高;丹江湿地国家级自然保护区内的主要人类活动影响为耕地,其次包括居民点、采石场、养殖场; 15年间,保护区内外土地覆被均呈现转好趋势,但是保护区内变化优于保护区外,保护区核心区优于整个保护区,且转好的主导因素均是耕地变为湿地; 15年间植被覆盖度变化较小。  相似文献   

8.
利用福州地区139个自动站2012—2020年逐时气温资料,对福州城市热岛时空结构进行研究并探讨其成因。结果表明,加密自动站清晰地展现了福州城市热岛的精细结构表现为“多中心”特征,即除了福州市中心城区的热岛主中心外,在闽清县城区和福清市城区还有两个副热岛中心,热岛强度在0.8 ℃~1.6 ℃之间。此外,除永泰及闽侯等山区呈负热岛外,大部地区呈正热岛。在城市热岛演变趋势上,福州郊区及山区大部呈减少趋势,呈增长趋势的区域仅分布在闽清、罗源沿海、永泰东部、中心城区、闽侯南部、福清北部、长乐南部、连江西部等地区,速率为每10 a 0 ℃~0.25 ℃。  相似文献   

9.
以射电望远镜(FAST)项目周边的平塘县、罗甸县为研究区域,利用遥感数据和“3S”技术手段,结合相关统计资料,从土地利用结构系统、土地利用程度系统、土地利用效益系统、土地利用可持续系统4个方面,选取18个指标构建土地利用结构合理度评价指标体系,运用ITOPSIS模型对研究区土地利用结构合理度进行定量评价。结果表明:研究区土地利用结构合理度较低,且存在时空变化差异。2000年、2005年、2013年平均土地利用结构合理度分别为27.45%、29.84%、17.76%,呈先增大后减小波动变化趋势;2000、2005年平塘县土地利用结构合理度均高于罗甸县,2013年略低于罗甸县。  相似文献   

10.
利用1985、2000、2013年遥感影像提取的土地覆盖数据,通过景观格局指数、动态度计算、转移矩阵等,分析1985—2013年我国典型地区各类型生态系统景观格局及其动态变化特征、生态系统相互转化时空变化特征等,揭示1985—2013年生态环境格局变化的特点和规律:一级分类生态系统综合变化率,赣江、闽江、白龙江和岷江上游流域分别为4.7%、3.9%、3.3%和1.7%,生态系统变化强度1985—2000年较缓,2000—2013年更剧烈。1985—2013年典型区生态系统的主要转化方向具有持续性和双向性特征,岷江、白龙江和赣江上游流域退耕还林还草政策效果明显,出现较高比例的耕地转为森林和草地;面积占67.4%生态系统类型变化与耕地生态系统和人工表面生态系统变化有关;生态系统变化具有明显的区域差异,生态变化主要表现为沿主要河流谷地的线状延伸,主要城镇居民点附近生态系统类型变化较为突出,人类活动是典型地区生态系统类型格局变化的主要驱动力;典型区尤其是敏感区应加大退耕还林还草政策,减少人类经济活动,降低洪水泥石流灾害发生的概率和程度。  相似文献   

11.
通过对兵团土地利用空间格局变化分析,选择合适的土地利用政策保护生态环境。运用RS和GIS技术对兵团近10年土地利用/覆被变化及景观格局空间变化进行分析,并在此基础上运用Markov模型对未来30年土地利用变化进行预测。2000—2010年,新疆生产建设兵团景观多样性升高,连通性增强,形状愈来愈简单,景观格局整体变化不大;草地、灌丛、湿地、荒漠和冰川/永久积雪面积减少,耕地和城镇面积增加,森林保持稳定;人为干扰对土地利用结构的变化具有重要作用,土地利用强度受人为活动影响的同时受土地利用政策影响;在未来30年间耕地和城镇面积继续增加,除森林基本保持不变外其他土地利用类型均减小。兵团城镇用地与草地和耕地之间的矛盾逐渐显现,势必引起兵团生态格局的变化。因此,必须实行合适的土地利用政策保护环境。  相似文献   

12.
The development activities in mountainous region though provide comfort to the human being and enhance the socioeconomic status of the people but create pressure on the bio-resources. In this paper, the current status of land use/landcover and the vegetation communities of the Solang valley watershed in Himachal Pradesh of Indian western Himalaya has been mapped and presented using remote sensing. This watershed area was dominated by alpine and sub-alpine pastures (30.34%) followed by scree slopes (22.34%) and forests (21.06%). Many tree, shrub, and herb species identified in the study area are among the prioritized species for conservation in the Indian Himalayan Region. Thus, scientific interventions and preparation of action plans based on ecological survey are required for conservation of the Solang valley watershed.  相似文献   

13.
Overuse of land resources has increasingly contributed to environmental crises in China. To mitigate widespread land degradation, actions have been taken to maintain and restore the ecological environment through efforts such as ecological engineering. By analyzing trends in land use, the impact and effectiveness of ecological engineering can be determined. In this study, such changes in Huanjiang County in China were considered. In the early 1990s, an eco-immigration policy and “returning farmland to forest program” were implemented in the county, drastically impacting land use. Land use/land cover changes were detected and analyzed using remote sensing data recorded over 4 years (1995, 2000, 2005, and 2010). Land transfer flow and the rate of land use change elucidated the extent of changes, while nuclear density analysis indicated spatial agglomeration. The results indicate that, over a period of 15 years, farmland area increased, while forest area decreased initially before subsequently increasing. From 1995 to 2000, the highest transfer flow was observed in the grassland to farmland conversion (79.34%). From 2000 to 2005, the transfer flow of conversions was the highest for forest to farmland (56.79%). Land use changes were not prominent from 2005 to 2010. Direct drivers of land use change exert obvious impacts on land use, and indirect drivers impact direct drivers that are then channeled through direct anthropogenic drivers (e.g., land use policies). We found that ecological engineering has a very significant impact on land use change, and that impact varies from region to region.  相似文献   

14.
为了科学评估北京市平原区造林工程的生态影响,利用高分卫星数据获取2018—2020年北京市平原区造林面积、分布及变化信息,分析了造林工程的空间格局特征,并采用形态空间格局分析(MSPA)方法及最小累积阻力(MCR)模型,构建了北京市平原区生态网络,通过情景模拟分析造林工程对生态源地、生态廊道产生的影响。结果显示,2018—2020年北京市平原区造林工程主要沿西北东南方向实施,实现了对原有林地资源分布不均衡问题的解决。热点建设区域为北部的延庆及东南部的通州、大兴,呈现由城市边界逐步向市中心蔓延的发展趋势。在不考虑其他因素对土地利用的影响的前提下,造林工程的实施使平原区林地面积增长了9.8%。通过情景模拟发现,造林工程的实施使生态网络向连通、完整、均衡方向发展。其中,生态源地面积增长了131.0 km2,主要生态源地连通性提升了41.1%,生态廊道的分布由主要分布在西北部山区向西北、东南两个方向均有密集分布转变。综上,造林工程的生态环境效应显著,造林工程的实施对生态环境质量改善具有重要意义。  相似文献   

15.
生态系统管理中生态环境评价的关键问题   总被引:3,自引:3,他引:0  
阐述了生态环境评价和生态系统管理的内涵以及两者之间的关系,对国内外生态系统管理中生态评价的类型和特征进行了总结,并分析了生态系统管理中生态评价的关键问题,即为生态系统管理者提供有效的决策支持信息。因此,为生态系统管理服务的生态环境评价中,管理者的配合和支持起着非常重要的作用;评价方法必须科学、可行;评价数据必须准确可靠,并且能够连续获得;评价结论尽量真实反映生态状况。  相似文献   

16.
There has been increasing concern in highlands of semiarid Turkey that conversion of these systems results in excessive soil erosion, ecosystem degradation, and loss of sustainable resources. An increasing rate of land use/cover changes especially in semiarid mountainous areas has resulted in important effects on physical and ecological processes, causing many regions to undergo accelerated environmental degradation in terms of soil erosion, mass movement and reservoir sedimentation. This paper, therefore, explores the impact of land use changes on land degradation in a linkage to the soil erodibility, RUSLE-K, in Cankiri–Indagi Mountain Pass, Turkey. The characterization of soil erodibility in this ecosystem is important from the standpoint of conserving fragile ecosystems and planning management practices. Five adjacent land uses (cropland, grassland, woodland, plantation, and recreational land) were selected for this research. Analysis of variance showed that soil properties and RUSLE-K statistically changed with land use changes and soils of the recreational land and cropland were more sensitive to water erosion than those of the woodland, grassland, and plantation. This was mainly due to the significant decreases in soil organic matter (SOM) and hydraulic conductivity (HC) in those lands. Additionally, soil samples randomly collected from the depths of 0–10 cm (D 1) and 10–20 cm (D 2) with irregular intervals in an area of 1,200 by 4,200 m sufficiently characterized not only the spatial distribution of soil organic matter (SOM), hydraulic conductivity (HC), clay (C), silt (Si), sand (S) and silt plus very fine sand (Si + VFS) but also the spatial distribution of RUSLE-K as an algebraically estimate of these parameters together with field assessment of soil structure to assess the dynamic relationships between soil properties and land use types. In this study, in order to perform the spatial analyses, the mean sampling intervals were 43, 50, 64, 78, 85 m for woodland, plantation, grassland, recreation, and cropland with the sample numbers of 56, 79, 72, 13, and 69, respectively, resulting in an average interval of 64 m for whole study area. Although nugget effect and nugget effect–sill ratio gave an idea about the sampling design adequacy, the better results are undoubtedly likely by both equi-probable spatial sampling and random sampling representative of all land uses.  相似文献   

17.
为了厘清改革开放以来忻州市各类生态系统及生态系统格局的时空特征,使用忻州全市1980、2000、2018年的土地利用和覆盖(LULC)二级分类数据,经过土地转移矩阵和景观格局指数计算,探讨分析了忻州市改革开放以来近40年的LULC及格局的长时间序列时空变化特征,以揭示忻州市的生态环境变化态势。研究区近40年来以城镇用地和其他建设用地增加为主,其他各类减少,城镇化和人口增长带来的土地和生态压力主要集中在草地、耕地以及湿地上;其中2000—2018年的变化更剧烈,人类活动对自然的干扰加剧,但同时在这一阶段已经开始了森林、湿地的保护,开展经济发展与生态文明同步建设。  相似文献   

18.
LANDSCAPE DEVELOPMENT INTENSITY INDEX   总被引:12,自引:0,他引:12  
  相似文献   

19.
Changing the landscape has serious environmental impacts affecting the ecosystem services, particularly in the tropics. In this paper, we report changes in ecosystem services in relation to land use and land cover over an 18-year period (1988--2006) in the Menglun Township, Xishuangbanna, Southwest China. We used Landsat TM/ETM and Quickbird data sets to estimate changes in ten land use and land cover categories, and generalized value coefficients to estimate changes in the ecosystem services provided by each land category. The results showed that over the 18-year period, the land use and land cover in the study area experienced significant changes. Rubber plantations increased from 12.10% of total land cover to 45.63%, while forested area and swidden field decreased from 48.73 and 13.14 to 27.57 and 0.46%, respectively. During this period, the estimated value of ecosystem services dropped by US $11.427 million (approximately 27.73%). Further analysis showed that there were significant changes in ecological functions such as nutrient cycling, erosion control, climate regulation and water treatment as well as recreation; the obvious increase in the ecological function is provision of raw material (natural rubber). Our findings conclude that an abrupt shift in land use from ecologically important tropical forests and traditionally managed swidden fields to large-scale rubber plantations result in a great loss of ecosystem services in this area. Further, the study suggests that provision of alternative economic opportunities would help in maintaining ecosystem services and for an appropriate compensation mechanisms need to be established based on rigorous valuation.  相似文献   

20.
On August 8, 2009, Typhoon Morakot brought heavy rain to Taiwan, causing numerous landslides and debris flows in the Taihe village area of Meishan Township, Chiayi County, in south-central Taiwan. In the Taihe land is primary used for agriculture and land use management may be a factor in the area’s landslides. This study explores Typhoon Morakot-induced landslides and land use changes between 1999 and 2009 using GIS with the aid of field investigation. Spot 5 satellite images with a resolution of 2.5 m are used for landslide interpretation and manually digitalized in GIS. A statistical analysis for landslide frequency–area distribution was used to identify the landslide characteristics associated with different types of land use. There were 243 landslides with a total area of 2.75 km2 in the study area. The area is located in intrinsically fragile combinations of sandstone and shale. Typhoon Morakot-induced landslides show a power–law distribution in the study area. Landslides were mainly located in steep slope areas containing natural forest and in areas planted with bamboo, tea, and betel nut. Land covered with natural forest shows the highest landslide ratio, followed by bamboo, betel nut, and tea. Landslides thus show a higher ratio in areas planted with shallow root vegetation such as bamboo, betel nut, and tea. Furthermore, the degree of basin development is proportional to the landslide ratio. The results show that a change in vegetation cover results in a modified landslide area and frequency and changed land use areas have higher landslide ratios than non-changed. Land use management and community-based disaster prevention are needed in mountainous areas of Taiwan for hazard mitigation.  相似文献   

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